Window Selector — Keyboard-Driven Alt+Tab Replacement for Windows

中文說明 (繁體)

A fast, zero-config Alt+Tab replacement for Windows 10/11. Press a hotkey to see live DWM thumbnails of every open window in a full-screen grid, then tap a letter key to switch instantly. Built in Rust with Direct2D.

Table of Contents

• Demo
• Features
• Why Window Selector?
• Download & Install
• Build
• Run
• Usage
• Configuration
• Architecture
• Contributing
• License

Demo

Screenshot coming soon — a demo GIF of the letter-select flow is in the works.

Features

• Live DWM Thumbnails — Real-time window previews rendered by the Desktop Window Manager, not static screenshots.
• Keyboard-First Navigation — Each window is assigned a home-row-first letter (A, S, D, F, G, H, J, K, ...). Press the letter to select, Enter/Space to switch.
• Number Tagging — Pin frequently used apps with Ctrl+1 through Ctrl+9. Tags persist across app restarts and resolve to the most recently used matching window.
• Quick List Bar — A compact strip at the bottom of the overlay showing all windows with their letter, number tag, and title at a glance.
• Multi-Monitor Support — Overlay spans all connected monitors with per-monitor grid layout.
• MRU Ordering — Windows are sorted by most-recently-used order, tracked in real time via a WinEvent hook.
• Accent Color Integration — Selection highlight uses the Windows system accent color.
• Aura Glow Effect — Selected cells have a 3-layer bloom glow for clear visual feedback.
• System Tray — Runs in the background with a tray icon. Right-click for Settings, About, or Exit.
• Configurable Hotkey — Default is Ctrl+Alt+Q. Change it in the Settings dialog or edit the config file.

Why Window Selector?

The built-in Windows Alt+Tab requires cycling through every open window one at a time — there is no keyboard shortcut to jump directly to the window you want. Window Selector replaces that workflow with a full-screen grid where every window gets a letter label: press the letter, confirm with Enter or Space, and you're there. No mousing, no cycling.

Tool	Letter navigation	Live thumbnails	Multi-monitor	Persistent tags	Open source
Built-in Alt+Tab	—	—	—	—	—
PowerToys (no equivalent)	—	—	—	—	✓
TaskSwitchXP	—	—	—	—	—
Window Selector	✓	✓	✓	✓	✓

Window Selector is the only free, open-source, single-binary option with home-row letter navigation and persistent number tags on Windows 10/11.

Download & Install

Grab a pre-built binary from the latest GitHub Release:

• Portable — window-selector.exe: no installation required.
• Installer — WindowSelector-<version>-setup.exe: NSIS installer with Start Menu integration.

Portable quick start:

1. Download window-selector.exe from the Releases page.
2. Place it anywhere on your system — no installation required.
3. Double-click to run. The application starts minimized to the system tray.
4. Press Ctrl+Alt+Q to open the window switcher overlay.

Windows Defender SmartScreen: Because the executable is not yet code-signed, Windows may show a SmartScreen warning on first launch. Click More info → Run anyway to proceed. The full source code is available in this repository for review.

Build

Requirements:

• Windows 10/11 (x86_64)
• Visual Studio 2022 Build Tools (MSVC toolchain)
• Rust stable toolchain

cargo build              # Debug build
cargo build --release    # Release build (LTO enabled)

The target triple is hardcoded to x86_64-pc-windows-msvc in .cargo/config.toml.

Run

cargo run                # Debug
cargo run --release      # Release

The application starts minimized to the system tray. Press the activation hotkey (default: Ctrl+Alt+Q) to open the overlay, or Win+Y for label mode.

Usage

Action	Key
Open overlay (full-screen grid)	Ctrl+Alt+Q (configurable)
Open label mode (quick labels)	Win+Y (configurable)
Select a window	Press the letter shown on its thumbnail/label
Switch to selected window	Enter or Space
Dismiss overlay	Escape
Tag a window's app with a number	Ctrl+1 through Ctrl+9 (while a window is selected)
Jump to the tagged app	1 through 9

Letter Assignment

Letters are assigned in an ergonomic home-row-first order:

a s d f g h j k l    (home row)
q w e r t            (top row left)
y u i o p            (top row right)
z x c v b n m        (bottom row)

The most recently used window gets A, the second gets S, and so on. Up to 26 windows can receive a letter.

Configuration

Config file: %APPDATA%\window-selector\config.toml

hotkey_modifiers = 16387   # MOD_CONTROL | MOD_ALT | MOD_NOREPEAT
hotkey_vk = 81             # VK_Q (Ctrl+Alt+Q for overlay)
label_hotkey_modifiers = 16392   # MOD_WIN | MOD_NOREPEAT
label_hotkey_vk = 89             # VK_Y (Win+Y for label mode)

[[quick_tags]]
number = 1
exe_path = 'C:\\Windows\\System32\\notepad.exe'

Logs are written to %APPDATA%\window-selector\logs\.

Architecture

Single-threaded Win32 message pump. All state lives on the main thread — no async runtime, no multi-threading. The keyboard-driven window switcher is implemented in Rust using the windows crate for Win32 bindings, Direct2D for rendering, and DWM for live thumbnails.

Module breakdown

Module	Purpose
main.rs	Entry point, message loop, window procedures
state.rs	OverlayState state machine (Hidden/FadingIn/Active/FadingOut)
overlay.rs	Overlay window management, show/hide with fade animation
overlay_renderer.rs	Direct2D + DirectWrite rendering (backdrop, cells, glow, quick list)
dwm_thumbnails.rs	DWM live thumbnail registration and letterboxing
grid_layout.rs	Aspect-ratio-driven grid computation
interaction.rs	Keyboard input handling (pure logic, returns KeyAction enum)
window_enumerator.rs	Window enumeration with Alt+Tab heuristic filters
letter_assignment.rs	Home-row-first letter sequence
mru_tracker.rs	Real-time MRU tracking via EVENT_SYSTEM_FOREGROUND
window_switcher.rs	Focus transfer with AllowSetForegroundWindow + fallback
animation.rs	Fade animator (80ms, ~60fps)
config.rs	TOML config with atomic writes
hotkey.rs	Global hotkey registration
tray.rs	System tray icon and context menu
monitor.rs	Multi-monitor enumeration
accent_color.rs	Windows system accent color reader
settings_dialog.rs	Settings dialog (Win32)
about_dialog.rs	About dialog (Win32)

Contributing

Issues and pull requests welcome. The codebase is single-threaded Win32; read CLAUDE.md for architecture notes before submitting a patch. For new features, open an issue first to discuss the approach.

License

MIT